Researchers have discovered a blood test that they say can predict with greater than 90 percent accuracy if a healthy person will develop mild cognitive impairment or Alzheimer’s disease within three years.
Described in Nature Medicine, the test identifies 10 lipids, or fats, in the blood that predict the onset of disease. According to researchers, the test could be ready for use in clinical studies in as few as two years.
“Our novel blood test offers the potential to identify people at risk for progressive cognitive decline and can change how patients, their families, and treating physicians plan for and manage the disorder,” said the study’s corresponding author Howard J. Federoff, M.D., Ph.D, professor of neurology and executive vice president for health sciences at Georgetown University Medical Center.
“While there have been many efforts to develop drugs to slow or reverse the progression of Alzheimer’s disease, all of them have failed,” noted Federoff. “One reason may be the drugs were evaluated too late in the disease process,” he added.
“The preclinical state of the disease offers a window of opportunity for timely disease-modifying intervention,” he said. “Biomarkers such as ours that define this asymptomatic period are critical for successful development and application of these therapeutics.”
The five-year study included 525 healthy people over the age of 70 who gave blood samples upon enrolling and at various points in the study.
Over the course of the study, 74 people met the criteria for either mild Alzheimer’s disease (AD) or a condition known as amnestic mild cognitive impairment (aMCI), in which memory loss is prominent. Of these, 46 were diagnosed upon enrollment and 28 developed aMCI or mild AD during the study, according to the researchers, who noted that the people in the latter group were called converters.
In the study’s third year, the researchers selected 53 participants who developed aMCI/AD, including 18 converters, and 53 cognitively normal matched controls for the lipid biomarker discovery phase of the study.
The researchers noted that the lipids were not targeted before the start of the study, but were an outcome of the study.
A panel of 10 lipids was discovered, which researchers say appears to reveal the breakdown of neural cell membranes in participants who develop symptoms of cognitive impairment or AD.
The panel was validated using the remaining 21 aMCI/AD participants, including 10 converters, and 20 controls. Blind data was analyzed to determine if the participants could be placed in the correct diagnostic categories based solely on the blood test, the researchers explained.
“The lipid panel was able to distinguish with 90 percent accuracy these two distinct groups: Cognitively normal participants who would progress to MCI or AD within two to three years, and those who would remain normal in the near future,” Federoff said.
He added the researchers consider the study’s results a “major step” toward a biomarker test that “could be useful for large-scale screening to identify at-risk individuals.”
“We’re designing a clinical trial where we’ll use this panel to identify people at high risk for Alzheimer’s to test a therapeutic agent that might delay or prevent the emergence of the disease,” he concluded.